The present invention pertains to stenographic machines. More particularly, the present invention pertains to a stenographic machine having electrically powered paper advance and manually actuated print hammers and in which the key stroke length can be controlled independently of the paper advance length.
Present day machine shorthand stenographers generally use manual stenographic machines for several reasons. First of all, in most applications, particularly in court reporting, it is essential that the operation of the machine be as quiet as possible. Heretofore, it has only been manual machines which have been able to operate sufficiently quietly for use in such circumstances. Secondly, stenographers often have to take notes in places where electrical service is non-existent, inconvenient, or unreliable.
Although electrically powered stenographic machines have been available for some time, they have not been widely used for the foregoing reasons, as well as others. Examples of such prior electrically powered stenographic machines are shown in Watson, U.S. Pat. No. 2,593,371, and Katz, U.S. Pat. No. 2,855,082. The machine of the Katz patent utilizes a large number of solenoids and a ratchet drive, all of which contribute to undesirably noisy operation. The Watson machine and also conventional manual machines have another drawback in that the paper advance length is directly related to the key stroke length. Thus, while the length of the paper advance is adjustable, the adjustment control for the paper advance also controls the distance by which the keys must be depressed during each stroke. Consequently in order to achieve a paper advance of sufficient length to space apart the notes taken on the machine by an amount making the notes easily readable, it is necessary to adjust the machine to a point at which the keys must be depressed an inordinate distance. Not only does this slow note taking and more rapidly tire the operator, but also it often results in "shadowing"--the inadvertent striking of an extraneous key, for example the inadvertent striking of a key with the ring finger when keying a note that calls for the middle finger and the little finger. The alternative adjustment, providing a shorter key stroke length, results in a shorter paper advance, making the notes more difficult to read. The action of the keys in advancing the paper has necessitated the interrelationship of these two features. Thus, heretofore, it has not been possible to get a desirably long paper advance without at the same time altering the necessary key depression distance to require an undesirably long key stroke.
In conventional manual stenographic machines, when taking notes at a high rate of speed, or with the machine adjusted to allow short key strokes, there is a danger of "stacking" of notes; i.e., writing characters on top of each other, resulting in unreadable notes. Additionally, conventional manual stenographic machines advance the paper during the downstrokes of the keys, just prior to the printing of a line of notes. A given line of notes thus is not visible to the operator until he writes the next line of notes, unless he stops and manually advances the paper.